Thomas btjujtt dixon



T. B. DIXON.

'TELEGRAPHY.

APPLICATIOI "LED III II. "Ii.

Patented Sept. 23, 1919 'Invento nutty as I.

THOMAS BULLI'I'T DHON, OF NEW YORK, N. Y.

TELEGRAPH.

Original application filed December 5, 1913, Serial No.

Specification of Letters Patent.

Patented Sept. 23, 1919.

804,873. Divided and this application filed July 13,

1916. Serial R0. 108,988.

T 0 all whom it may concern:

Be it known that I, THOMAS Bunnrrr Drxon, citizen of the United States of America, and a resident of New York city, county and State of New York, have invented certain new and useful Improvements in Telegraphy, of which the following is a spec' cation.

My invention relates to improvements in what may be termed selenium relays, z. 0., instruments wherein a pencil of light, defiected variably by the influence of current pulses upon a movable member of an electric instrument, is caused to sweep across the surface of a selenium cell or across the surfaces of a plurality of coacting selenium cells, thereby varying the resistance of such selenium cells and so varying the resistance of a circuit or circuits connected to such selenium cells and so actuating an instrument or instruments located in such circuits. In terming the device embodying the present invention a selenium relay I do not intend to limit myself to the use of a selenium cell or selenium cells; for it is known that other substances than selenium are affected as to electrical qualities by variation of illumination; actinium is one such substance, and other substances are lmown to have similar properities; nor do I intend to limit myself to the use of light as the particular variety of radiant energy employed. Thermo couples may be used in lieu of selenium cells, in which case heat rays may be employed in lieu of light rays; and it is well known that heat rays may be reflected and refracted in the same manner and by the same means as light rays. In fact, I have found it desirable to use the term radio-electro-sensitive element as comprehensive of various devices such as selenium cells, thermo couples, etc., which are affected as to electrical qualities (resistance, current generation, etc.) by radiant energy such as light or heat. However, selenium relays are the most commonly known devices of the nature to which my invention relates.

Therefore, in the following descri tion, I will refer to the selenium cells or e ements specifically, it being understood that the principles described herein are applicable to other forms of radio-electro-sensitive devices; and similarly I will refer to light specifically as the type of radiant energy employed, though it will be understood that the heat rays may be acted upon in a preclsely similar manner.

My invention comprises a radio electric relay (s ifically a selenium relay) wherein a plurality of encils of radiant energy are derived from t e same condensing lens, are PI'OJBCtBd therefrom upon the movable reflector of a primary actuating device adapted to be controlled by current pulses in a suitable controlling circuit, and from such reflector are projected each upon a radioelectro-sensitive device or pair of such devices, and by the action of such primary actuating device are caused to move across the surfaces of such radio-electrosensitive device or devices, in unison, thereby varying an electrical quality (resistance, current generation, etc.) whereby another instrument in the circuit of such radio-electro-sensitive device or devices is actuated. My invention also comprises a condensing lens interposed between the said primary actuating device and the said radio-electro-sensitive device or devices and of such nature that the beams or pencils of radiant energy are condensed in one direction without interference with the movement of such beams or pencils in a direction at right angles to the direction of condensation.

The object of my invention is to increase the efficiency of radio electric relays of the type referred to.

I will now proceed to describe my invention with reference to the accompanying drawing showing diagrammatically apparatus embodying my invention, and will point out the novel features in claims.

The said drawing shows diagrammatically a primary actuating device, means for producing a plurality of beams of radiant energy coincident upon such primary actuating device and reflected therefrom as two separate beams of radiant energy upon two pairs of radio-electro-sensitive devices, together with a condensing lens interposed between the said radio-electro-sensitive devices and said primary actuating device, and arranged to condense such pencils of radiant ener in one direction without interfering wit quality of such radio-electrosensitive devices, due to the varying action of radiant energy thereon.

In the said drawing 1 designates a primary actuatin device comprising a co 6, of the genera nature of a galvanometer coil, having a fiber nsicn 5 and located in the field of force of magnet poles 4 and connected by traces 10 to a light member 8 having a fiber suspension 9 and carrying a light reflector 7. 11 designates a source of radiant energy (the particular source shown beingl the carbons of an electric arc lamp) an 12 shows a pair of condensing lenses (these lenses being sectioned horizontally to show their characteristic shape) while 13 indicates a screen intersed between said condens' lenses 12 and the primary actuating device reflector 7, such screen having two apertures 13* of a shape adapted to produce light beams of the desired cross sectional shape.

14, 14", 14 and 14 designate radio-electro-sensitive devices (specifically selenium cells) in the paths of the light pencils reflected from primary actuatmg device reflector 7. In the arrangement shown these selenium cells are rectangular, and such rectangular shape is preferable in most cases. There being two apertures 13 in the screen 13, there are two 1' ht pencils incident upon these selenium ce s, and in the normal or rest position of primary actuating device reflector 7, each light pencil will be, usually, half upon one selenium cell and half upon an adjacent selenium cell; there being two selenium cells for each light pencil. As each light pencil incident u on the selenium cells moves (and both lig t pencils move together) the illumination 0 one cell of each pair will decrease while the illumination of the other cell of each air will increase. By means hereinafter escribed the decrease of illumination of one cell of each pair (whereby the resistance of that cell is increased) and the increase of illumination of the companion cell of each pair (whereby the electrical resistance of that cell is decreased) are caused to exert a cumulative or additive result upon the instrument actuated by such selenium cells.

For various practical reasons allof the light from a condensing lens or pair of condensing lenses, such as the lenses 12, cannot be utilized. While the light beams or ncils ma be shaped to a considerable an very use 1 extent by a further shaping lens such as the lens 15 hereinafter mentioned, yet the pencil or pencils of light incident upon the reflector 7 must for best results have some relation to the shape of the selenium cells employed; furthermore, for best results, such beams of light must be sharply defined at their margins, particularly those margins, the positions of which shift with the movement of the reflector 7. For these reasons it is necessary to shape the light pencil o1 pencils, at or near the condensers 12, by some means, such for example as the screen 13. But while for best results the light pencil employed should be narrow, yet it is possible to take a plurality of such light pencils from a single condenser or pair of condensers; for which reason the screen 13 is shown as provided with two light apertures 13 each of a proper shape to produce a light pencil of the desired cross section. These light pencils impinge coincidently upon the reflector 7, and, being reflected thereby, diverge and each strike the surfaces of a pair of selenium cells.

In order that the light pencils employed may permit the utilization of a large proportion of the light projected from the condensing lenses 12, it is desirable that the light apertures in the screen 13 be of as great hei ht as they may be and yet be filled by the lig t from such lenses. The resulting light pencils would be, in general, of greater height, where such 1' ht encils impinge .upon the selenium ce ls, t an the height which it is desirable that such selenium cells should have, were it not for the employment, between such selenium cells and the primary actuating device reflector 7, of the condensing lens 15. An ordinary spherical condensing lens may not be employed, to best advantage, at this oint, because such a lens, if amp 0 ed, will interfere with the movement of t e pencils of light across the surfaces of the selenium cells, greatly reducing the amplitude of movementas compared with the amplitude of movement obtained if no such condensing le'ns be present. But a cylindrical condensin lens placed as shown has no influence of t at nature. On the other hand it produces condensation of the light 0' or pencils in a direction at right ang es to the direction of movement of such light pencils, and thus permits the condensation of such light pencils, in a direction at right angles to the direction of movement (5. 6., in a vertical direction, in the arrangement shown) so asto bring those light pencils within the surface limits of the se enium cells, and makes the illumination of the cells correspondingly of greater intensity, this increase in intensity of illumlnation greatly improving the operation of the apparatus. Of course, adjustment of the posltion of lens 15 will vary the height of the light pencils where incident upon the selenium cells.

Various circuit arrangements may be employed to permit the cumulative action of the various selenium cells in the operation of the actuated instrument, 20. In my prior application Serial No. 804,873, filed Decemn n 178. TELEGRW her 5, 1913, of which this is a division, I have indicated various such circuit arrangements, and therefore in the present instance I have thoughtit necessary to indicate one arrangement only, wherein the several cells 14*, 14", 14, and 14 are connected in a Wheatstone bridge arrangement, the coil 21 of a receivin instrument (of the general nature of a ga vanometer, and which in practice is usually a siphon recorder) being included in the cross-wire 2022 of the Wheatstone bridge.

30 indicates the pole pieces of the magnets creating the magnetic field in which coil 21 is located. This coil is shown as provided with an ordinary fiber suspension 31.

What I claim is 1. A radio-electric relay comprising in combination radio-electro-sensitive means, a primary actuating device comprising a reflector adapted to cause one or more pencils of radiant energy to move across such radioelectric-sensitive means, and means for projecting convergently into coincidence on such reflector a plurality of pencils of radiant energy, the said pencils, b reason of their convergent relation as inci ent pencils, being reflected divergently from such reflector, said radio-electro-sensitive means being located to intercept the said reflected pencils and to be influenced by movement of such pencils, and electromagnetic means controlled by such radio electro-sensitive means.

2. A radio-electric relay comprising in combination a plurality of radio-electrosensitive means, a primary actuating device comprising a reflector adapted to cause pencils of radiant energy to move across such radio-electro-sensitive means, means for projecting convergently from a single source into coincidence on such reflector a plurality of pencils of radiant energy, the said pencils, by reason of their convergent relations as incident pencils, being reflected divergently from such reflector, said radio-electro-sensitive means being located to intercept the said reflected pencils and to be influenced by movement of such pencils, and electro-magnetic means controlled by said radio-electro-sensitive means.

3. A radio-electric relay comprising in combination a plurality of pairs of radioelectro-sensitive means, a primary actuating device comprising a reflector adapted to cause pencils of radiant energy to move across said radio-electro-sensitive means, and means for projecting convergently from a single source into coincidence on such reflector a plurality of pencils of radiant energy, the said pencils by reason of their convergent relation, as incident pencils, being reflected divergently from such reflector, each of said pairs of radio-electro' sensitive means being located to intercept energy on the other radio-elcctro-sensitive means of each pair.

4. A radio-electric relay comprising in combination a plurality of radio-electrosensitive means, a primary actuating device comprising a reflector adapted to cause one or more pencils of radiant energy to move .across such radio-electro-sensitive means, a

source of rays of radiant energy, condensing means therefor adapted to concentrate rays from such source upon said reflector, a screen interposed in the path of such rays and comprising a plurality of apertures which convert the said rays into a plurality of pencils of radiant energy convergent into coincidence on such reflector, the said pencils, by reason of their convergent relation as mcident lpencils, being reflected divergently from. suc i reflector, as a plurality of reflected pencils, the said radio-electro -sensitive means being located so that each such means intercepts one of the said reflected pencils in a manner to be influenced by movement of that pencil, and electromagnetic means controlled by such radio-electro-sensitive means.

5. A radio-electric relay comprising in combination radio-electro-sensitive means, a primary actuating device comprising a reflector adapted to cause a pencil of radiant energy to move across such radio-electrosensitive means, means for projecting upon such reflector a shaped pencil of radiant energy which is reflected divergently from such reflector, condensing means in the path of the reflected pencil arranged to condense such reflected pencil in a direction at right angles to the direction of motion of such pencil due to motion of such reflector, but not to interfere with motion of such pencil, said radio-electro-sensitive means being located to intercept the reflected pencil after passage through such condensing means, and electro-magnetic means controlled by such radio-electro-sensitive means.

6. A radio-electric relay comprising in combination radio-electro-sensitive means, a primary actuating device comprising a reflector adapted to cause a pencil of radiant energy to move across such radio-electrosensitive means, means for pro]ecting upon such reflector a shaped pencil of radiant energy which is deflected divergently from such reflector, a cylindrical condensing lens in the path of said reflected pencil and having its axis in the plane of movement of such pencil, said radio-electro-sensitive 5 means being located to intercept the reflected pencil after passage through such condensing lens, and electro-magnetic means con- ,trolled by such radio-electro-sensitive means.

7. A radio-electric relay comprising in 10 combination radio-electro-sensitive means of that, except for the condensing action of such lens the dimension of such pencil, in a direction at right angles to its plane of movement, would exceed the corresponding dimension of the radio-electro-sensitive means at the point of incidence of such pencil upon such means, said condensing lens adapted to mndense such reflected ncil, in the direction at right angles to its direction of movement, to bring such pencil within the corresponding dimension of such radio-electro-sensitive means, and electro-magnetic means controlled by such radio-electro-sensitive means. v In testimony whereof I have signed this specification in the presence of two subscribing, witnesses.

' THOMAS BULLITT DIXON.

Witnesses:

ARTHUR R. RULLEY, E. N. Cooim.

Copies of this patent my be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. (2.

Dixon 1,19

Dixon 1,19

sass 250- a 7,451 17sas 

